Window, Muntin and Method

ABSTRACT

A non-metal window muntin formed from plastic or wood is described for use in hermetically sealed insulated glass windows. The process for forming the muntin includes machining polystyrene sheets which are painted with a latex pain and baked prior to use between sealed glass of the window.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuation application of co-pending U.S. Ser. No.11/981,400 filed Oct. 31, 2007, which is a continuation application ofU.S. Ser. No. 11/296,962 filed Dec. 7, 2005, which is a continuationapplication of reexamination Ser. No. 90/006,818, which had issued asU.S. Pat. No. 6,415,579, from a divisional application of applicationSer. No. 08/957,498 filed Oct. 24, 1997, entitled WINDOW, MUNTIN ANDMETHOD, now U.S. Pat. No. 5,980,667.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention pertains to a decorative window muntin contained betweentwo hermetically sealed panes of glass and a method for making the same.

2. Description of the Prior Art and Objectives of the Invention

In recent years, glass making and installing has progressed to allowlarge panes of window glass to be installed, whereas, previously, smallpanes were individually framed and supported within a window structureknown by those in the industry as true divided lite (TDL). This TDLarrangement became unnecessary with utilization of large panes. Forexample, whereas, previously, a one meter by one meter window glass mayhave been made of nine individual panes of glass, now one pane is used.

While the science of glass and window making was advancing to allowlarger panes of glass to be used, similar advances occurred in energyefficient windows, and hermetically sealed insulated glass windows havebecome increasingly popular. Such windows have parallel spaced panes ofglass to provide insulation and increase energy conservation. Thesewindows are commonly referred to as having insulated glass (IG) as twonormal panes of glass are combined to form one pane of IG.

In an effort to make the appearance of the new IG windows match olderwindows, decorative muntins formed from metal are placed between thepanes of glass in IG. These muntins do not provide any support; they arepurely decorative. In this manner the IG windows look like TDL windowswhile providing the insulative properties desired by today's windowowners and fabricators.

Problems sometimes arise in IG windows as strong sunlight or heatedtemperatures raise the temperature inside the sealed glass. Moisture inthe muntin vaporizes and often recondenses on the inside surface of theglass pane, causing a fog-like effect which “clouds” the glass. Becausethe glass is sealed, cleaning or rubbing will not remove this clouding.The escape of moisture or liquid from the muntin is commonly referred toas “outgassing” and has been the cause of much dissatisfaction in thewindow fabrication and installation industry. Likewise, this problem hasrequired the replacement of many IG windows which become opaque withmoisture.

While outgassing is less of a problem with conventional aluminummuntins, another problem arises in the manufacture of aluminum muntinsfor use in IG windows. Aluminum can be difficult to bend using presenttechnology, and some shapes are just not possible to create usingaluminum. This is important in oddly shaped windows. Where aluminum canbe used, it is frequently a multipiece assembly which raisesmanufacturing and assembly costs.

Other problems arise in the expansion and contraction of conventionalmuntins as they undergo temperature changes in installed windows. Somemuntins expand too rapidly when heated and buckle within the IG. Atother times when the expanded muntin attempts to contract, the warp orbuckle has become permanent and is unsightly.

Therefore with these and other problems known, it is an objective of thepresent invention to provide a muntin for use in an IG window which doesnot cause or allow outgassing.

It is a further objective of the present invention to provide a muntinwithin an IG window which is pleasing to the consumer's eye.

It is still a further objective of the present invention to provide amuntin which is easy to manufacture through the use of Computer AidedDesign (CAD) tools.

It is another objective to provide a muntin with low expansioncharacteristics and which has high memory.

It is yet another objective to provide an abrasive resistant muntinwhich is inexpensive to manufacture.

It is still a further objective to provide a one piece muntin that isready to be placed within a window without additional assembly steps.

It is yet a further objective to provide a method of making a muntinwith the above described characteristics.

Various other objectives and advantages of the invention will becomereadily apparent to those skilled in the art upon further reference tothe detailed description below.

SUMMARY OF THE INVENTION

The aforesaid and other objectives are realized by a window muntinmachined from a non-metal material, preferably polystyrene, althoughpolyurethane or wood may be acceptable, which is easily machined usingCAD technology. The machined muntin is painted with a latex paint andbaked until the moisture is removed and the paint has dried. The bakedmuntin is then placed between two panes of glass and hermetically sealedtherein as is usual in the art. This glass unit is then available formounting in a conventional window assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a front elevational view of the preferred embodiment of thedecorative muntin of the invention;

FIG. 2 illustrates a bottom plan view of the muntin along lines 2-2 ofFIG. 1;

FIG. 3 demonstrates a front elevational view of the muntin of FIG. 1mount between panes of glass in an IG window;

FIG. 4 features a cross-sectional view of the window of FIG. 3;

FIG. 5 depicts an alternate embodiment of a muntin in a pane ofinsulated glass mounted in a window; and

FIG. 6 shows a cross-sectional view of the window of FIG. 5 along lines6-6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS AND OPERATION OF THEINVENTION

Turning now to the drawings, specifically FIGS. 1 and 2 show decorativewindow muntin 10, the preferred embodiment. Non-metal window muntin 10is preferably machined from a 0.476 cm thick sheet of polystyrene,although other polymeric or non-metal materials such as polyurethane orwood may be acceptable, into a desired shape such as the radial displayseen in

FIG. 1, although other shapes and designs can be employed. Window muntin10 includes a plurality of arms 11, each including end 12. Placed intoeach end 12 is cylindrical pin 13, which is preferably formed fromaluminum 0.238 cm in diameter and 1.27 cm long. Pins 13 are received bycylindrical channels 14 which are preferably 0.238 cm in diameter and0.635 cm deep, so that approximately one-half the length of each pin 13extends from each channel 14. Pin 13 is centrally located on end 12 foroptimum stability. Paint layer 15 (FIG. 2) completely surrounds andcoats window muntin 10. Paint layer 15 is preferably conventionalpigmented latex paint. It is within the scope of the present inventionto use conventional clear or unpigmented sealants such as a polyurethaneor other varnishes in place of paint 15.

After window muntin 10 is painted and heat cured as explained in thepreferred method below, it is ready to be placed in insulated window 20as seen in FIGS. 3 and 4. Insulated window 20 comprises two parallel,opposing conventional glass plies 21 and 21′ disposed in conventionalwooden or aluminum window frame 25. Glass plies 21 and 21′ are spacedone from the other by conventional sealant 22, such as a two partpolyurethane finish which hermetically seals plies 21 and 21′ together.Spacer 24, formed from rolled aluminum preferably from 1.27 cm to 1.905cm thick hold plies 21 and 21′ apart and is placed inside, but flushagainst sealant 22, and includes a number of cylindrical channels 23equal to the number of pins 13 on muntin 10 and spaced around spacer 24according to the location of pins 13 on muntin 10. Channels 23 are,preferably, 0.238 cm in diameter and 0.635 cm deep to accommodate pins13 as best seen in FIG. 4. As can be easily understood, pins 13 holdmuntin 10 in the proper position when placed and secured in channels 23and 14. Spacer 24 and muntin 10 are sandwiched between glass plies 21and 21′ as sealant 22 hermetically seals muntin 10 therein as isconventional and well understood in the art.

Window muntin 30, an alternate embodiment, is shown in FIGS. 5 and 6.Muntin 30 includes arms 31 with pins 32 much like muntin 10. Pins 32 fitinto channels 33 of arms 31 and channels 41 of spacer 42. Glass plies 43and 43′ sandwich muntin 30 therebetween and are sealed with sealant 44.Frame 45 surrounds and obscures sealant 44 and spacer 42 from normalvision. Likewise, pins 32 are hidden from normal vision by muntin 30. Itis to be understood, that while not shown, muntin 30 also has a layer ofpaint surrounding and sealing muntin 30 to prevent outgassing.

While only two embodiments of the present invention are shown, it is tobe understood that any number of configurations or geometrically shapedwindows, and muntins sized to fit such windows are possible and withinthe scope of the present invention. While glass is the preferredtransparent ply, other plies such as polyacrylic, polycarbonates or thelike may be used. The spacer would be resized and the channels in thespacer rod would be repositioned to accommodate the pins. Likewise,there is no particular muntin cross section preferred. A simplerectangle is shown in FIG. 2, but other conventional shapes arecontemplated.

In the preferred method of making decorative window muntin 10, a crosssection is chosen such as rectangular cross-section seen in FIG. 2. Thedimensions of this cross-section are programmed into a conventional CADprogram that can be downloaded into a three to five axis CNC router (notshown) such as those sold by CR Onsrud Inc. of Huntersville, N.C. Aplanar sheet of high impact polystyrene, preferably 0.476 cm thick andof a size large enough to accommodate the desired pattern orconfiguration is placed on a cutting table (not shown) and secured. Thecutting unit on the router is then engaged and the desired pattern iscut, so that an unfinished, but machined muntin 10 is created.

Using a conventional electric drill (not shown) with a 0.238 cm diameterdrill bit, channels 23 are drilled 0.635 cm deep into the center of ends12 of muntin 10. Pins 13 are inserted and secured in ends 12 with aconventional adhesive. Muntin 10 is cleaned using a conventional solventsuch as an ethyl or other alcohol solution to remove any dust or oilsfrom the cutting procedures. Muntin 10 is then coated with aconventional water-based latex paint such that layer of paint 15 isformed thereon. This is preferably done in a conventional spray booth.All sides of muntin 10 should be so coated with a light to medium coatof paint and allowed to completely air dry.

After drying, muntin 10 is then preferably heat cured or baked at220.degree. F. or 104.4.degree. C. for twenty to thirty minutes so as toforce the gases contained within muntin 10 to be driven out or be sealedtherewithin. By this procedure, only an extremely low percentage ofvolatiles remains which can later cause outgassing. Muntin 10 is thenplaced between two plies of glass 21 and 21′ as earlier described and ishermetically sealed or sandwiched between plies of glass 21 and 21′ foruse in a conventional window, such as window 20.

The preceding recitation is provided as an example of the preferredembodiment and an alternate embodiment for illustrative purposes and isnot meant to limit the nature or scope of the present appended claims.Variations of the invention are anticipated by those skilled in the art.

1. A decorative window muntin made by a process comprising the steps of:providing a non-metal polymeric planar member; constructing a unitaryone-piece muntin having no connecting joints and having at least threeends; and coating the constructed muntin with a heat cured coating,wherein said heat cured coating prevents the escape of remainingvolatiles from said constructed muntin upon heating.
 2. The muntin ofclaim 1, wherein the coating step comprises the step of coating theconstructed muntin with a latex paint.
 3. The muntin of claim 1, whereinthe providing step comprises the step of providing a polystyrene member.4. The muntin of claim 1, wherein the providing step comprises the stepof providing a polyurethane member.
 5. A window made by a processcomprising the steps of: providing a first pane of glass; providing asecond pane of glass; providing a unitary one-piece decorative muntinwith no connecting joints, said muntin including at least three ends,said muntin comprising a heat cured coating layer; placing said muntinbetween said first pane of glass and said second pane of glass; andhermetically sealing the muntin between said first pane of glass andsaid second pane of glass.
 6. The window of claim 5, further comprisingthe step of: coating the muntin with a latex paint prior to placing saidmuntin between said first pane of glass and said second pane of glass.7. The window of claim 5, wherein the polymeric muntin comprises apolystyrene material.
 8. The window of claim 5, wherein the polymericmuntin comprises a polyurethane material.
 9. A muntin for use in awindow, said muntin being made by a process comprising the steps of:providing a unitary one-piece muntin with no connecting joints having atleast three ends, said planar member adaptable to conform to the window;and covering the polymeric planar member with a heat cured coating,wherein said heat cured coating prevents the escape of remainingvolatiles from said planar member upon heating.
 10. The method of claim9, wherein the covering step comprises the step of covering thepolymeric planar member with a latex paint.
 11. The method of claim 9,wherein the providing step comprises the step of providing a polystyrenemember.
 12. The method of claim 9, wherein the providing step comprisesthe step of providing a polyurethane member.
 13. A window made by aprocess comprising the steps of: providing a pane of glass; providing aunitary one-piece muntin with no connecting joints, said muntincomprising a heat cured coating layer; placing said muntin adjacent tosaid pane of glass and said second pane of glass.
 14. The window ofclaim 13, wherein the process further comprises the step of: coating themuntin with a latex paint.
 15. The window of claim 13, wherein thepolymeric muntin comprises a polystyrene material.
 16. The window ofclaim 13, wherein the polymeric muntin comprises a polyurethanematerial.
 17. The window of claim 13, wherein the step of placing amuntin in a window further comprises the step of fixedly attaching saidmuntin to said window.